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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19692 results found.

  1. EP241115a: EP detection of a fast X-ray transient
  2. GRB 241115A: Swift detection of a burst
  3. EP 241113a: LBT possible optical counterpart
  4. GRB 241113A: PRIME near-infrared upper limits
  5. GRB 241113B: J-band upper limit from WINTER
  6. GRB 241113A: J-band observations with WINTER
  7. EP241113a : J-band observations with WINTER
  8. GRB 241030A: LCO optical observation
  9. GRB 241113B: Swift-XRT observations
  10. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  11. EP241113b/GRB 241113B: EP detection of GRB 241113B
  12. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  13. GRB 241113A: Swift/UVOT Detection
  14. GRB 241113A: REM detection of the optical/NIR afterglow
  15. GRB 241113B: Swift ToO observations
  16. GRB 241113A: LCO optical observations
  17. GRB 241112B: GMG Optical Upper Limit
  18. GRB 241113A: Enhanced Swift-XRT position
  19. GRB241113A: LCOGT (40-cm) optical counterpart detection
  20. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  21. GRB 241113A: Swift detection of a burst with an optical counterpart
  22. SVOM/GRM detection of a short burst from SGR 1E1841-045
  23. GRB 241112B: AbAO optical upper limit
  24. GRB 241107A: GROWTH-India telescope optical upper limit
  25. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  26. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  27. GRB 241112B: Mephisto optical upper limits
  28. GRB 241112B: GOTO optical upper limits
  29. GRB 241112B: Swift ToO observations
  30. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  31. GRB 241107A: INTEGRAL IBIS localization
  32. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  33. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  34. IPN triangulation of GRB 241107A (short/hard)
  35. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  36. GRB 241018A: cubesat Avion detection
  37. LIGO/Virgo/KAGRA S241109bn: Upper limits from EP-WXT observations
  38. LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations
  39. INTEGRAL detection of a burst from 1E 1841-045
  40. EP241107a: AbAO optical upper limit
  41. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  42. EP241107a: KAIT optical observations
  43. GRB 241108A: Swift ToO observations
  44. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  45. EP241107a: Kinder optical follow-up observations
  46. GRB 241025A: radio detection with the VLA
  47. EP241107a: AKO Optical Afterglow Follow-Up Observations
  48. GRB 241105A: SVOM/GRM observation
  49. EP241107a: OHP/T193 photometric and spectroscopic observations
  50. GRB 241105a: PRIME near-infrared upper limits
  51. GRB 241105A: ePESSTO+ NTT optical afterglow detection
  52. EP241107a: GIT optical observations
  53. EP241107a: SVOM/C-GFT optical observations
  54. EP241107a: AKO Optical Afterglow Detection
  55. GRB 241025A: LBT optical observations
  56. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  57. GRB 241105A: Swift/UVOT Detection
  58. GRB 241105A: Swift-XRT afterglow detection
  59. GRB 241104A: Swift-XRT observations
  60. GRB 240511A: LCO upper limits
  61. GRB 241105A: Swift ToO observations
  62. GRB 241104A: Swift ToO observations
  63. GRB 241104A: SVOM/VT optical candidate
  64. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  65. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  66. EP241104a: EP detection of GRB 241104A X-ray emission
  67. GRB 241010A: host galaxy redshift z = 0.977
  68. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  69. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  70. GRB 240821A: further radio observations with the VLA
  71. EP241103a: GIT optical upper limit
  72. EP241021a: OHP/T193 further optical observations
  73. LIGO/Virgo/KAGRA S241102br: OHP/T193 optical observations
  74. EP241103a: Swift XRT detection and improved X-ray position
  75. EP241021a: continued SOAR observations
  76. EP241101a: Optical upper limits with Kinder observations
  77. EP241101a: OHP/T193 optical observations
  78. EP241103a: EP observation update
  79. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  80. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  81. EP241103A: LCO optical observations
  82. EP241103a: an X-ray transient detected by Einstein Probe
  83. S241102cy: Identification of a GW compact binary merger candidate
  84. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  85. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  86. GRB241030A: OHP/T193 optical observations
  87. GRB 241101A: FRAM-ORM optical limit
  88. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  89. GRB 241030A: further SAO RAS optical observations
  90. GRB 241030A: Optical Observations via Virtual Telescope Project
  91. EP241021a: Liverpool Telescope optical follow-up observations
  92. GRB 241026A: SAO RAS optical observations
  93. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  94. EP241021a: OHP/T193 optical observations
  95. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  96. GRB 241030B: Montarrenti Observatory optical upper limit
  97. EP241026b: Liverpool Telescope optical follow-up
  98. GRB 241030A: SAO RAS optical observations
  99. EP241021a: AMI-LA radio detection
  100. GRB 241030B : GIT optical upper limits

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